Battle of Callao, 1866: Spain's fleet against the guns of Peru

The war had begun with an incident far from any battlefield. ABC's historical archive recalls that in 1864 Spain seized Peru's guano-rich Chincha Islands to force the Peruvian government to investigate the killing of Spanish workers. Chile, Ecuador and Bolivia joined Peru, and the conflict known in Spain as the Pacific campaign dragged on for two years. In March 1866 the Spanish squadron bombarded the undefended port of Valparaíso in Chile, one of the most controversial episodes of the war.²

Callao was a different matter. The research center of the Chilean Navy, which published a study of the battle on its anniversary in 2026, notes that unlike Valparaíso, Callao was ready. Its defenses were coastal batteries of mixed calibers, among them modern Armstrong 300-pounders whose shot could pierce iron plate of up to 19 cm, while the Numancia's armor was no more than 13 cm thick. The people of Lima and Callao poured into the port to help, and one heavy Blakely gun, still remembered as the People's Gun, was dragged into place by thousands of volunteers.³

An admiral who ignored his orders

ABC tells the story that on the eve of the attack a junior officer, Pedro Álvarez de Toledo, brought Méndez Núñez the government's order to break off and return to Spain. The admiral is said to have replied that the officer had not arrived yet: he would arrive on the 3rd, after Callao had been bombarded. The date was chosen, both sources note, because 2 May was the anniversary of Madrid's rising against Napoleon in 1808, and because Spain wanted to answer the charge that it had attacked only a defenseless town.⁴

The Spanish squadron numbered the ironclad frigate Numancia and the wooden frigates Blanca, Resolución, Berenguela, Villa de Madrid and Almansa, with the schooner Vencedora. The Chilean study counts about 251 guns; ABC gives 270 against 69 on the Peruvian side, 56 ashore and 13 in a few ships.⁵

Five hours of fire

Morning fog lifted to reveal the port. At about noon the Numancia fired the first shot. ABC records the Peruvian secretary of war, José Gálvez, waiting in the Merced tower to let the Spaniards fire first, and then ordering the batteries to reply. Within half an hour Méndez Núñez fell wounded on the Numancia's bridge; the ship's captain, Juan Bautista Antequera, wrote that the admiral insisted on staying at his post until he fainted from loss of blood.⁶

The Spanish ships suffered badly. In the Chilean study, drawing on the account of a Spanish sailor, the Villa de Madrid was crippled early by a 300-pound shot and towed out of action. A shell set the Almansa on fire near her magazine, and her captain refused to flood the powder. The Berenguela, holed below the waterline, kept firing until a hit set her coal bunkers alight and she had to withdraw. The Blanca stood close inshore until she had used up her ammunition.⁷

The Peruvians lost heavily too. About 55 minutes into the battle an explosion in the Merced tower killed 27 men, among them Gálvez himself, ABC writes. By late afternoon the fire slackened on both sides. Around five o'clock the Spanish ships still in action drew off toward San Lorenzo island; the last shots of the day came from the Peruvian Junín tower and the monitor Victoria, in the Chilean account, while the Spanish remembered only three Peruvian guns still answering.⁸

Two victories

The verdicts still diverge. Spain held that the squadron had silenced the batteries and saved its honor; Méndez Núñez told his crews they had humbled the enemy behind his stone walls. In Peru, 2 May is a national holiday and the defense of Callao a founding memory. The Chilean study judges that neither claim holds fully: the Peruvian guns were not silenced, no Peruvian ship was taken and the port works survived, but the defenders sank no Spanish ship either.⁹

The Spanish squadron buried its dead on San Lorenzo, about 43 by the study's count, with some 151 wounded; ABC gives Peruvian estimates ranging from 80 or 90 to an implausible 2,000. Part of the squadron then sailed for the Philippines, and the Numancia, crossing the Pacific, became the first ironclad to sail around the world. Spain and the four South American states signed an armistice in 1871.¹⁰